What do nitrates do in angina management?

What do nitrates do in angina management?

• A. They increase heart rate.
• B. They donate nitric oxide, causing vasodilation and reduced myocardial oxygen demand.
• C. They reduce afterload by renal adjustment.
• D. They block calcium channels.

Answer: (B)

Nitrates donate nitric oxide, which relaxes vascular smooth muscle and causes vasodilation. This effect is strongest in the veins, leading to venodilation that lowers preload and LV filling pressures. With less wall stress, the heart consumes less oxygen for the same amount of work, so myocardial oxygen demand falls and angina is relieved. At higher doses some arterial dilation can occur and may reduce afterload, but the main therapeutic action in angina is the decrease in oxygen demand from reduced preload. They do not work by blocking calcium channels or by renal adjustments.

Nitrates donate nitric oxide, which relaxes vascular smooth muscle and causes vasodilation. This effect is strongest in the veins, leading to venodilation that lowers preload and LV filling pressures. With less wall stress, the heart consumes less oxygen for the same amount of work, so myocardial oxygen demand falls and angina is relieved. At higher doses some arterial dilation can occur and may reduce afterload, but the main therapeutic action in angina is the decrease in oxygen demand from reduced preload. They do not work by blocking calcium channels or by renal adjustments.